#include <stdio.h>

int main() {
    int a = 0;
    int b = 0;
    int c = 0;
    while (scanf_s("%d%d%d", &a, &b, &c) != EOF)
    {

        if ((a + b > c && a - b < c) && (a + c > b && a - c < b) && (b + c > a && b - c < a))
        {
            if (a == b && b == c)
            {
                printf("Equilateral triangle!\n");
            }
            else if (a == b || a == c || b == c)
            {
                printf("Isosceles triangle!\n");
            }
            else {
                printf("Ordinary triangle!\n");
            }
        }
        else {
            printf("Not a triangle!");
        }
    }


    return 0;
}